(a) Field of the Invention
The present invention relates to a method and apparatus for transmitting and receiving a signal based on interference of the signal.
(b) Description of the Related Art
Generally, in an orthogonal frequency division multiplexing (OFDM) system, a shape and a speed of a pulse are determined in order to transmit a signal in an allowed bandwidth without inter-symbol interference. This is called a Nyquist-based pulse generating method. A pulse determined according to the Nyquist-based pulse generating method may have a maximum transfer rate in a given bandwidth without the inter-symbol interference.
FIG. 1 is a view illustrating a plurality of pulses generated according to the Nyquist-based pulse generating method.
Referring to FIG. 1, each pulse is transmitted without inter-symbol interference. Namely, a currently transmitted symbol is generated according to the Nyquist-based pulse generating method, whereby a generated symbol is transmitted without interfering with preceding and subsequent symbols
When it is assumed that a transmitted symbol values are [1, −1, 1, −1, −1], the transmitted signal is denoted by the bold solid line. Namely, the bold solid line signal has the values [1, −1, 1, −1, −1] without inter-symbol interference at times 0, Ts, 2Ts, 3Ts, 4Ts. Here, Ts denotes a period between symbols according to the Nyquist-based pluse generating method.
However, the Nyquist-based pulse generating method has a limitation in terms of a transfer rate, and in order to mitigate this problem, a faster than Nyquist (FTN)-type pulse generating method has been introduced. The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.